In many optical setups parabolic mirrors are used to direct a light beam towards a target and to redirect the beam reflected by the target to a detector assembly. To optimize performance, the parabolic mirrors need to be in near-perfect alignment with both the target and the detector assembly. To achieve this positioning, many parabolic mirrors use an adjustable mounting assembly. The mounting assembly has adjusting mechanisms adapted to adjust the parabolic mirrors in both azimuth and elevation. Once the parabolic mirrors are in the proper azimuthal and elevational directions, a locking mechanism in each direction is used to lock the parabolic mirrors in position. The locking mechanisms, however, can act on the adjusting mechanisms, moving the parabolic mirrors out of alignment. Once the parabolic mirrors are out of alignment, the light beam is not aimed directly at the target, which also affects the reflected beam.